Method and apparatus for applying a glass collet to a cathode-ray tube

ABSTRACT

A method and apparatus for attaching a neck collet to the neck stub of a cathode-ray tube funnel utilizing a single axial reference in a manner that the axis of the collet coincides with the axis of the funnel perpendicular to the sealing edge. The sealing edge of the open funnel is positioned on a rotatable funnel support means which has a hollow axial spindle shaft oriented perpendicular to the support means and affixed thereto. Slidably oriented within the spindle shaft is a center shaft formed to extend through the funnel and protrude beyond the neck stub thereof. Collet holding means, associated with the terminal portion of the center shaft, insures positive concentric alignment of the collet with the neck stub since the axes are coincident.

United States Patent Gordon S. Patrick Lelpslc, Ohio 17,819

Mar. 9, 1970 Sept. 21, 1971 lnventor Appl. No. Filed Patented Assignee Sylvania Electric Products Inc.

Continuation of appiicatiou Ser. No. 691,365, Dec 118, 1967, now abandonegl.

METHOD AND APPARATUS FOR APPLYING A GLASS COLLET TO A CATHODE-RAY TUBE 4 Claims, 2 Drawing figs.

US. Cl 65/28, 65/36, 65/56, 65/57, 65/167, 65/271, 65/323, 316/2 Int. Cl. C03c 27/00 Field of Search 65/28, 36,

[56] References Cited UNITED STATES PATENTS 2,923,097 2/1960 Hollinger 65/348 Primary ExaminerS. Leon Bashore Assistant Examiner-J B. Hardaway Att0meys-Norman J. OMalley, Donald R. Castle and Frederick H. Rinn ABSTRACT: A method and apparatus for attaching a neck collet to the neck stub of a cathode-ray tube funnel utilizing a single axial reference in a manner that the axis of the collet coincides with the axis of the funnel perpendicular to the sealing edge. The sealing edge of the open funnel is positioned on a rotatable funnel support means which has a hollow axial spindle shaft oriented perpendicular to the support means and afiixed thereto. Slidably oriented within the spindle shaft is a center shaft formed to extend through the funnel and protrude beyond the neck stub thereof. Collet holding means, associated with the terminal portion of the center shaft, insures positive concentric alignment of the collet with the neck stub since the axes are coincident.

METHOD AND APPARATUS FOR APPLYING A GLASS COLLET TO A CATHODE-RAY i 3i.

REFERENCE TO RELATED APPLICATION BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for attaching a collet to the mating portion of an open article and more particularly to a method and apparatus for precisely attaching a neck collet portion to the mating neck stub portion of an open cathode ray tube funnel. While it is recognized that the invention is applicable to effect aligned jointure between mated parts of a number of open ended glass, plastic and metal articles, it has been particularly useful in renecking cathode-ray tube funnels and such usage will be described herewith.

Cathode-ray tubes employed in television and other display applications conventionally utilize an envelope comprising a glass face panel joined to a funnel portion which is also usually of glass. One or more electron guns are positioned within the neck portion of the funnel in a manner to beam electrons toward a cathodoluminescent screen associated with the face panel. Since the glass envelope represents considerable monetary value, it is desirable to salvage and reuse as much of the glass envelope structure from inoperative tubes as economically feasible. In the shadow mask type of color cathode-ray tubes, it has been found that the face panel can be separated from the funnel portion in a practicable manner, thereby allowing reuse of both portions if such be structurally sound. Salvaging of the funnel portion also involves removal of the electron gun herefrom which necessitates severing the neck of the tube. Thus, before the funnel portion can be reused, a new neck collet must be joined thereto in a properly aligned manner.

A conventionally utilized previous method of renecking cathode-ray tube funnels used a vertical lathe involving two separate shafts which rotated at substantially the same speed. A lower shaft arrangement accommodated the funnel portion and an upper shaft had a clamping attachment for holding the new neck collet. The two shaft arrangements were brought together in a manner that the neck collet could be joined to the neck stub portion. By use of separate and independent shafts for locating and rotating the neck collet and funnel portions, it was extremely difficult to precisely align and maintain concentricity of the pieces during fusion. The lack of alignment and concentricity of the renecked funnels resulted in a high rejection of tubes because of poor quality. The misaligned or eccentric collet to funnel relationship caused improper positioning of the internally oriented electron gun and the externally neck-located beam deflection components.

OBJECTS AND SUMMARY OF THE INVENTION It is an object of the invention to reduce the aforementioned disadvantages and to provide a method and apparatus for achieving optimum alignment of the neck collet with the neck stub of the funnel portion.

Another object is the provision of a method and associated apparatus for renecking cathode-ray tube funnels that can be accomplished in either a vertical or horizontal position.

The foregoing objects are achieved in one aspect of the invention by utilizing a method and apparatus wherein a rotatable funnel support table has an axial spindle shaft afiixed perpendicularly therethrough. Concentrically related to the spindle shaft is a post means formed to extend through the neck stub portion of the funnel. Collet holding means, associated with the terminal portion of the post means, protrudes from the neck stub and provides positive concentric alignment of the collet with the funnel during the placement and fusion operations since the axes of the collet and funnel are coincident.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of the apparatus of the invention showing a salvage funnel positioned thereon for neck stub preparation; and

FIG. 2 is a sectional view of a portion of the apparatus showing the collet and funnel positioned for sealing.

DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following specification and appended claims in connection with the aforedescribed drawings.

With reference to the drawings, there is shown in FIGS. 1 and 2 an apparatus 11 for attaching a collet portion to the mating portion of an open article having a longitudinal axis perpendicular to the plane of the seating edge of the article. In this instance, the apparatus lll is utilized to reneck a cathoderay tube funnel 13 having a sealing rim 15, a neck portion 17, and a longitudinal axis 18.

The apparatus 11 has a rotatable funnel support means or table 19 having a support surface 21 upon which the sealing rim 15 of the funnel is oriented to facilitate rotation of the funnel 13 about its longitudinal axis 18. The funnel support means or table 19 has an axis 23 and an integral hollow spindle shaft 25 which is affixed perpendicularly through the support table 19 to facilitate axial rotation thereof. The spindle shaft is rotatably supported within a stationary spindle housing 27 by suitable bearings such as cone and cup roller bearing assemblies 29, one of which is shown. The stationary spindle housing is suitably mounted on support frame means 31. Rotational movement is provided to the support table 19 by rotation means 33. Such means may take the form of a sheave 35 affixed to the spindle shaft 25, a motor 37, with a drive sheave 39, and a drive belt 41 connecting the respective sheaves. The rotation of the motor is predeterminately controlled by switch means 43.

A hollow center shaft 45, concentrically telescoped within the hollow axial spindle shaft 25, is formed to rotate with said spindle shaft by a spline 44 and key 46 relationship thereby effecting predetermined sliding longitudinal movement within the spindle shaft in a manner that a portion of the center shaft is extended therefrom as an axial post perpendicular to the funnel support table 19. The collet holding means is a chuck arrangement 47 associated with the terminal portion 49 of the center shaft 45. This chuck is of the expanding type and for example comprises a plurality of similarly shaped individual contacting members 51 which are longitudinally arranged about a chuck support member 48. These members 51 are formed to move radially outward in an expanding manner from vertical seating on the chuck support member 48 of the center shaft 45 to provide holding contact with the inner wall of the collet.

The center shaft 45 is moved in a predetermined sliding longitudinal manner along axis 23 by center shaft movement means 53 to properly position the collet holding means 47 during the funnel-renecking operation. The movement means 53 may be one of several conventional combinations such as a dual plate arrangement comprising a first plate 55 and a related second plate 55' which are formed to slide as a unit on at least two stationary guide rods 57. Racks 59 and associated pinions 61 are related to the dual plate arrangement 55 and 55' to effect sliding movement thereto. The rotations of related pinions 61 are compatibly synchronized by power means 63, with the desired activation being controlled by switching means 65.

Attached to the first plate 55 of the dual arrangement is a bearing block 67 having a bearing 69 therein to form a rotational seat for the center shaft 45. The bearing block provides attachment of the center shaft with the movement means 53 which effects longitudinal movement of the center shaft within the spindle shaft 25.

A nonrotational enter expander shaft '71, having a diameter smaller than the internal dimension of the hollow center shaft 45 is positioned within the hollow shaft in a manner to have predetermined slidable longitudinal movement therein. The expander shaft is formed of a length to extend through the center shaft with one end being terminally fashioned to actuate movement of the contacting members 51 of the collet holding means 47. As shown this expander shaft 71 has a shaped termination 73 attached to the end thereof as by afiixation means 76. This termination is formed, for example, as an inverted truncation having a smooth circumferential surface 72 which mates in a slidable manner with compatibly angled end surfaces 75 of the individual collet contacting members 51 to provide sliding low friction contact therebetween. A similar angled sliding surface relationship exists between the opposite end surfaces 75 of the contact members and mating center shaft circumferential seat 74 which is part of the chuck support member 48. The several contacting members 51 have upper grooves 50 which relate to each other as do the lower grooves 52. This respective relationship provides two substantially circumferential grooves into which expandable resilient means or springs 54 are fitted. Retraction of the expander shaft effects substantially longitudinal sliding movement along the mated angular surfaces 72, 75 and 74, 75' to shift the contacting members radially outward away from seating on the chuck support member 48 to a collet holding position. When the expander shaft is moved longitudinally in an upward direction, resilient means 54 contract thereby retracting the contacting members radially inward from collet holding contact. The expander shaft 71 is attached by means not shown to a movable support shelf 77 which is slidable in channel 79 in bracket 81; the bracket being attached to the bearing block 67. Longitudinal reciprocation of the expander shaft is effected by shaft movement means 83, which in this instance comprises an air cylinder 85, actuated by control means 87 from supply 89, with the opposing movement furnished by spring tension means 91.

Air required to properly form the collet seal is supplied from supply 89 through valving 93, thence through a port 95 in the bearing block 67 to connect with an annular groove 97 therein. The hollow center shaft has at least one port 99 in line with the annular groove 97 to provide a continuous supply of air to the interior spacing 101 of the rotating center shaft 45. This interior spacing functions as a longitudinal conduit to convey air to the chuck support member 48 at the terminal portion of the hollow center shaft 45 which is in the area of the collet seal adjacent the collet holding means 47. One or more exhaust ports 103 in the chuck support member 48 at the terminal portion of the center shaft 45 carry the air outward into an annular baffle space 105 formed in the chuck support member 48 and enclosed by a discretely apertured shield 107 which disperses the air at the collet seal area to facilitate proper forming of the seal.

The support surface 21 of the rotatable table 19 has center shaft protective means 109 attached in axial relationship thereon. Also, affixed to the support surface are several funnel locating means, two of which are shown, 111 and 111', formed to cooperate with the flare portion 14 of funnel 13 adjacent the sealing rim thereof to position the funnel in a manner that the axis 18 thereof is coincident with the axis 23 of the support table. In greater detail, the locating means 111 is of a type predeterminately affixed to the support table while the associated clamping locating means 111' provides sufficient clearance to facilitate placement and removal of the funnel. Both types of locating means are formed, for example, in a manner to lend support to the flare portion of the funnel thereby providing retention of the funnel on the support table should the apparatus be oriented in either a vertical or horizontal position.

Positioned above the rotatable support table 19 are cutoff means 113 for removing the undesired portion 112 of the tube neck to form the neck stub portion compatible for jointure with the new neck collet 127. The cutoff means comprises an air-gas mixing manifold 114 oriented on shaft 115 of fluid cylinder 116 in a manner that the cutoff flame 117 can be moved into and out of operational positioning in relation to the neck portion 17, such being controlled by means not shown. The cutoff means 113 is oriented on bracket 118 having height adjustment means 119 to provide precise positionmg.

Also positioned above the support table 19 are sealing means 120 comprising a manifold 121 mounted on shaft 122 of fluid cylinder 123 by which the sealing flame 124 is moved into and out of collet-neck sealing orientation by means not shown. The sealing means support bracket 125 has height adjustment means 126 to effect precise positioning for accomplishing the desired seal.

With reference to FIG. 1, the method of renecking comprises a number of sequential steps. With the collet holding means 47 substantially retracted within the protective means 109, the cathode-ray tube funnel 13 is positioned on the rotatable support table 19 by locating means 111 and the clamping counterpart 111'. In this manner the funnel sealing rim l5 rests in contiguous contact on the support surface 21 of the table 19 with the longitudinal axis of the funnel being coincident with the axis of the support table. Drive motor 37 is actuated to initiate rotation of the funnel support table. Cutoff means 113 is positioned and activated to direct the cutoff flame 117 to remove the old neck portion 112 thereby providing a funnel neck stub portion 20 having an accurate sealing edge 110. Upon removal of the undesired neck portion, the cutoff means 1 13 is inactivated.

With particular reference to FIG. 2, collet holding means 47, which is associated with center shaft 45, is raised to protrude through the neck stub portion 20 of funnel 13 by activating center shaft movement means 53. The neck collet portion 127 is positioned on the rotating collet-holding means 47 whereupon the contacting members 51 are moved radially outward to effect holding of the collet. The holding movement of the contacting members is brought about by effecting a retraction of the center expander shaft 71 through the activation of shaft movement means 33. The axis of the supported collet is coincident with the axis of the funnel 13 and perpen' dicular to the plane of the sealing rim 21. The collet 127 is moved in a predetermined manner along the longitudinal axis 18 so that the sealing edge thereof and that of the neck stub portion 20 are in contiguous relationship by activating the center shaft movement means 53.

Sealing means 120 is moved into the operational position as shown in FIG. 2, the sealing flame 124 being directed on the collet and neck edges. In the process of effecting the seal therebetween, the collet holding chuck 47 is raised and lowered about 0.200 of an inch to puddle the molten glass to strengthen and form the seal 128; whereupon, the sealing heat is removed and air injected through the apertured shield 107 directly at the seal area to force the seal 128 outward to the desired controlled shape. As aforedescribed, the air for this purpose is supplied from source 89 through valving 93 and thence through the interior spacing 101 of the center shaft 45 to the exhaust ports 103 adjacent the seal area.

Upon completion of the seal, rotation of the funnel support table 19 is stopped, collet holding means released and substantially retracted into the protective means 109, and the renecked funnel removed from the apparatus.

Thus, there is provided an improved method and apparatus for achieving optimum alignment of the neck collet with the neck stub portion of the funnel. The apparatus can accomplish the funnel renecking operation in either a vertical or horizontal position wherein the sealing edge of the funnel is positioned and supportingly retained on a rotatable support table during the procedure. A center shaft formed perpendicularly and axially from the support table is fashioned to extend through the neck stub and hold a collet portion in concentric alignment with the neck stub.

It is within the keeping of the invention for the renecking apparatus to utilize a stationary funnel support table and an associated sealing means formed to be rotatable about the collet-neck sealing area, or one that is formed in a manner to encompass the sealing area as a uniform heat emanator.

While there have been shown and described what are at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.

I claim:

1. A method for heat sealing a neck collet portion to a mating neck stub portion of a cathode-ray tube funnel having a longitudinal axis perpendicular to a plane formed by a sealing rim terminating a flare portion thereof, said method utilizing a funnel support means having funnel-locating means thereon and an integral axial hollow shaft affixed perpendicularly through said support means, said shaft having related hollow post means formed to extend therethrough and through said funnel in a manner to protrude from the neck stub thereof, said hollow post means having longitudinally formed colletholding means associated with the terminal portion thereof and means for supplying seal-forming air thereto, said method comprising the steps of:

positioning said funnel in an inverted manner with said sealing rim resting on said funnel support means, said post means being axially oriented therein;

moving said post means axially from said funnel through said neck stub to position said collet-holding means therebeyond;

positioning said neck collet portion on said longitudinally formed collet-holding means extending through said funnel with the axis of said collet being coincident with the axis of the funnel and perpendicular to the plane of the sealing rim thereof;

moving said collet in a predetermined axial manner along said longitudinal axis to effect jointure relationship between said collet and said mating neck stub portion;

applying sealing heat to said collet and said stub portion at substantially the jointure area thereof the provide axial collet location perpendicular to the plane of said sealing rim; and

supplying seal-forming air through said hollow post means to the seal area adjacent to said collet-holding means.

2. An apparatus for attaching a neck collet portion to a mating neck stub portion of a cathode-ray tube funnel having a longitudinal axis perpendicular to a plane formed by a sealing rim terminating a flare portion thereof, said apparatus comprising:

rotatable funnel support means having an axis and a support surface for orienting said funnel on said sealing rim thereof and rotating said funnel about said longitudinal axis;

a hollow axial spindle shaft affixed perpendicularly through said support means on said axis thereof to effect rotation of said rotatable funnel support means, said spindle shaft having a fixed key thereon;

a hollow center shaft concentrically telescoped within said axial spindle shaft, said center shaft having a spline thereon to cooperate with said spindle shaft key to effect center shaft rotation with said spindle shaft and have predetermined sliding longitudinal axial movement therein to extend therefrom as an axial post protruding through said neck stub;

funnel-locating means on said support means cooperating with the flare of said funnel adjacent said sealing rim to axially position said funnel on said funnel support means;

collet-holding means associated with the terminal portion of said center shaft to provide positioning of said collet in a contiguous aligned relationship to the neck stub portion of said funnel; said holding means being a plurality of longitudinally formed contacting members formed to move radially in an expanding manner to provide longitudinal holding contact with the inner wall of said collet; a nonrotatable center expander shaft positioned within said hollow center shaft and formed to have predetermined slidable longitudinal movement in an axial manner therein, said shaft having a termination formed to actuate movement of said longitudinal contacting members;

means for moving said center expander shaft to provide said predetermined slidable longitudinal movement to said expander shaft to actuate said collet-holding means; means for longitudinally moving said center shaft to orient said collet-holding means to provide contact and effect sealing positioning said neck collet and said neck stub;

rotation means for effecting common rotational movement of said funnel support means and said collet-holding means;

means for sealing said neck collet to said neck stub portion of said funnel; and

means for supplying seal-forming air to the terminal sealing region adjacent said longitudinal collet-holding means,

3. An apparatus according to claim 2 wherein a longitudinal space is provided between said hollow center shaft and said expander shaft to convey seal-forming air from a supply inlet to the sealing area.

4. An apparatus according to claim 2 wherein said funnellocating means is formed to retain the funnel on aid funnel support means when said apparatus is in either a vertical or horizontal position.

P0405) UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 7, 174 Dated September 1971 lnventofls) Gordon 8. Patrick It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 34, "herefrom" should read therefrom Column 3, line 1, "enter" should read center Column 5, line 39 of Claim 1, "the" second instance should read --to-- Column 6, line 47 of Claim 4, "aid" should read said Signed and sealed this 28th day of March 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

2. An apparatus for attaching a neck collet portion to a mating neck stub portIon of a cathode-ray tube funnel having a longitudinal axis perpendicular to a plane formed by a sealing rim terminating a flare portion thereof, said apparatus comprising: rotatable funnel support means having an axis and a support surface for orienting said funnel on said sealing rim thereof and rotating said funnel about said longitudinal axis; a hollow axial spindle shaft affixed perpendicularly through said support means on said axis thereof to effect rotation of said rotatable funnel support means, said spindle shaft having a fixed key thereon; a hollow center shaft concentrically telescoped within said axial spindle shaft, said center shaft having a spline thereon to cooperate with said spindle shaft key to effect center shaft rotation with said spindle shaft and have predetermined sliding longitudinal axial movement therein to extend therefrom as an axial post protruding through said neck stub; funnel-locating means on said support means cooperating with the flare of said funnel adjacent said sealing rim to axially position said funnel on said funnel support means; collet-holding means associated with the terminal portion of said center shaft to provide positioning of said collet in a contiguous aligned relationship to the neck stub portion of said funnel; said holding means being a plurality of longitudinally formed contacting members formed to move radially in an expanding manner to provide longitudinal holding contact with the inner wall of said collet; a nonrotatable center expander shaft positioned within said hollow center shaft and formed to have predetermined slidable longitudinal movement in an axial manner therein, said shaft having a termination formed to actuate movement of said longitudinal contacting members; means for moving said center expander shaft to provide said predetermined slidable longitudinal movement to said expander shaft to actuate said collet-holding means; means for longitudinally moving said center shaft to orient said collet-holding means to provide contact and effect sealing positioning said neck collet and said neck stub; rotation means for effecting common rotational movement of said funnel support means and said collet-holding means; means for sealing said neck collet to said neck stub portion of said funnel; and means for supplying seal-forming air to the terminal sealing region adjacent said longitudinal collet-holding means.
 3. An apparatus according to claim 2 wherein a longitudinal space is provided between said hollow center shaft and said expander shaft to convey seal-forming air from a supply inlet to the sealing area.
 4. An apparatus according to claim 2 wherein said funnel-locating means is formed to retain the funnel on aid funnel support means when said apparatus is in either a vertical or horizontal position. 